1. Field of the Invention
The invention relates to an enhanced enclosure arrangement for a computer, such as a deskside personal computer, and in particular, to an enhanced enclosure arrangement that accommodates therein a backplane, processor cards, input/output cards, memory riser cards, cooling devices and a power supply, for example.
2. Background Information
Computer systems typically have internal components that are disposed within a cage. For example, it is known to place an assembly, including a backplane and various circuit boards, such as a processor card, an input-output card and a so-called memory riser card, within an open cage. This forms a so-called central electronics complex (CEC) of a computer system. The cage is subsequently fixed within a computer housing.
The cage serves to position the circuit boards within the computer housing, and acts as an EMC (electromagnetic compatible) shield. An EMC shield allows operation in an electromagnetic environment at an optimal level of efficiency, and allows static charges to be drained to a frame ground. Moreover, the cage helps to protect the components contained therein from environmental damage, for example, vibrations, which could cause the components to fail.
Conventionally, the backplane, which is wiring board, is typically provided with card slots for the various circuit boards. The respective circuit boards may be removably coupled to the backplane by inserting a corresponding plug connector on the circuit board into the associated backplane card slot. The circuit boards are then held in place using various known means. For example, the circuit boards may be provided with latches disposed on their respective edges, which engage with catches disposed on the walls of the cage.
In order to allow the circuit boards to be connected to the backplane, it is also typical to position the backplane at a rear of the cage, and in a vertical position. This allows the circuit boards to be plugged into the card slots of the backplane through the open front, for example, of the cage. However, due to the weight of the circuit boards, this arrangement may create a rotational force at the card slot of the backplane, stressing the respective connections. Moreover, vibrations or other environmental forces may cause the respective circuit boards to disengage with the associated card slots of the backplane, causing the circuit board to become non-functional. Thus, there is a need for an arrangement that will prevent or hinder the circuit boards from inadvertently disengaging with the backplane.
Further, it is often desirable to place various ones of the circuit boards, for example the memory riser cards, in different orientations within the cage. For example, in one configuration, respective first and second memory riser cards may be disposed immediately adjacent to the opposite faces of an input/output (i.o.) card, for example. However, the typical memory riser card is provided with a plurality of removable Dual In-Line Memory Modules (DIMMs), which can be inserted into electrical slots provided on a front surface of the card. Since the DIMMs project away from the front surface, the DlMMs prevent the front surface from being placed immediately adjacent to the respective face of the i.o. card. On the other hand, the rear surface of the memory riser card is usually free of such projecting components. By positioning the rear surface of the memory riser card adjacent to the face of the i.o. card, the memory riser card can be placed closer thereto, thus saving desirable space and increasing performance by reducing signal path lengths, for example.
As such, since the rear surface of the memory riser card is the preferred surface to be disposed adjacent to the i.o. card, it is conventional to arrange the first and second memory riser cards in orientations that are 180xc2x0 opposite to each other. That is, one memory riser card must be rotated 180xc2x0 relative to the other memory riser card, so that the rear surfaces of the respective memory riser cards face each other, for example, and face the adjacent i.o. card.
However, in the conventional arrangements, if the same type of memory riser card is used for both orientations, the plugs on the memory riser cards, and the card slots in the backplane must be symmetrically configured. That is, the card slots must be centered from the front of the cage to the back of the cage. This would allow the same type of memory riser card to be used regardless of the required orientation of the card.
However, due to wiring arrangements on the backplane, for example, it may not always be possible to symmetrically locate the card slots for the memory riser cards. Thus, it also known to provide so-called right- and left-hand memory riser cards. These cards have their card plugs offset between a front edge and a rear edge of the card, to match an offset of the card slots in the backplane. For example, the right-hand card has the card plug offset toward a front of the card, and the left-hand card has its card plug offset toward a rear thereof. Thus, the right-hand memory riser card can be utilized on a right-hand side of the i.o. card, for example, and the left-hand card can be used on the left-hand side of the i.o. card.
As will be appreciated, by requiring two different types of memory riser cards, the total number of different parts that need to be manufactured is increased, thus increasing tooling times and costs, and increasing inventory. Thus, there is a need for an arrangement that will allow the same type of circuit board, for example a memory riser card, to be utilized in either a left-hand or a right-hand orientation, with a backplane that has offset card slots.
Additionally, the cage is typically fixed within a so-called system chassis, which is a frame that provides further support for the cage, and which is removably stacked upon other system chassises within a system rack. The chassis may contain other components and sub-systems, such as power supplies and cooling fans, for example, which are connected to the components within the cage using cables, for instance.
When the cage is removed from the chassis for service, typically the connections between the cage components and the other components within the system chassis must be manually disconnected and reconnected. This is a relatively time consuming process. Thus, there is a need for an arrangement that will allow for the removal of the cage for servicing, for example, which does not require manually connecting and disconnecting various electrical connectors.
Further, typically the circuit boards have an elongated, rectangular configuration, with a height (from a top edge of the board to a bottom edge of the board) that is greater than their depth (from a rear edge of the board to a front (card slot) edge of the board). In order to accommodate the circuit boards, the cage has a height (i.e., the direction in which the circuit boards longitudinally extend) that is dictated by the height of the circuit boards. Thus, the cage typically has a height that is greater than its depth. This likewise requires that the system chassis have a height that is sufficient to accommodate the cage. However, the system rack usually determines the overall height of the computer. Since it is also typical to stack the system chassises on top of each other, the system rack can thus only accommodate therein a set number of system chassises. Thus, there is a need for an arrangement that will accommodate an increased number of system chassises without increasing a height of the system rack.
The system chassis typically has an opening that allows access into an interior thereof. The opening is conventionally positioned at a top of the chassis, within a horizontal plane. However, and as previously mentioned, since it is also typical to stack the system chassises on top of each other, the opening may be inaccessible. Thus, when a component within the system chassis needs to be accessed, for repair or upgrading, for example, the chassis is conventionally removed from the system rack. This removal process is time consuming.
Moreover, because the system chassis must be removable, the chassis may not be as rigidly connected to the system rack as may otherwise be desired. Thus, the components within the chassis may be subjected to undesirable shocks and vibrations. Thus, there is a need for an arrangement that allows access to all of the components contained within a chassis, while the chassis remains fixed within the system rack.
Additionally, it is also typical to arrange a removable EMC shield between a periphery of the cage and the inner walls of the system chassis. The EMC shield protects against electromagnetic interference, and allows static charges to be drained to the system ground during the installation and removal of the processor cards, i.o. cards and memory riser cards.
In order to access the circuit boards within the cage, it is conventional to remove the shield. However, this disadvantageously increases the number of loose parts during servicing of the cage components. Moreover, since the shield must be realigned relative to the cage and the system chassis, installation times are increased. Thus, there is a need for an arrangement that allows the cage to be accessed without separately removing the EMC shield.
It is, therefore, a principle object of this invention to provide an enhanced enclosure arrangement for a computer.
It is another object of the invention to provide an enhanced enclosure arrangement for a computer that solves the above mentioned problems.
These and other objects of the present invention are accomplished by the enhanced enclosure arrangement for a computer disclosed herein.
According to one aspect of the invention, a cage is provided that has side walls that have a height (i.e., a distance from a bottom of the cage to a top of the cage) that is greater than their respective lengths (i.e., a distance from the front wall to the rear wall). Further, the cage is dimensioned to accommodate a backplane, a memory riser card, an i.o. card and a processor card. When received within the cage, the backplane closes off an open bottom of the cage, and serves as a floor of the cage, with the printed circuit board of the backplane facing into the cage.
The memory riser card and the i.o. card are likewise generally planar, rectangular structures, with lengths that are greater than their heights. As previously mentioned, the cage can then be advantageously tailored in the same manner (with a length that is greater than its height), so as to receive the respective cards therein with a minimum of wasted space. This advantageously allows more cages to be disposed in the same amount of space in a vertical direction than could otherwise be accomplished using the conventional cages.
The memory riser card and the i.o. card are preferably removably coupled to the backplane by inserting a known corresponding plug connector on the respective card into an associated backplane card slot. As will be appreciated, since the cage is open at its top, the cards are inserted through the open top and moved in a vertical direction until the cards engage with the associated card slots. This configuration advantageously uses gravity to help hold the cards in position. That is, the weight of the respective cards urges the cards in a direction toward the backplane. Thus, the memory riser card and the i.o. card are less likely to inadvertently disengage with the backplane.
In a further exemplary embodiment of the present invention, one or more of the card slots of the backplane may be offset relative to the front and rear walls. For example, the card slots for the memory riser cards may be positioned closer to the rear wall of the cage than to the front wall, in order to reduce the wiring lengths to an associated port disposed in the tailstock, or for other wiring reasons.
In order to eliminate the need for different right-hand and left-hand memory riser cards, a spacer is advantageously provided on either the front wall or the rear wall of the cage, to which the memory riser card can be attached. That is, the spacer is located against the respective wall that is furthest away from the respective offset card slot, so as to cause the card slot to be symmetrically arranged (i.e., centered) between the spacer and the other wall. Thus, this exemplary embodiment allows the same type of memory riser card, for example, to be utilized in either a left-hand or a right-hand orientation, with a backplane that has offset card slots.
Since the cards may be modified by the user, in a further advantageous exemplary embodiment of the present invention, the cards are easily accessible within the cage. As previously discussed, the cards are accessed through the open top of the cage. Further, the chassis has a space in which the cage can be disposed, and has an open rear through which the cage may be accessed. The cage may be removed from the chassis through the open rear without removing the chassis from a rack. This advantageously allows the chassis to be permanently affixed within the rack, and ensures that the components disposed within the chassis will not be subjected to undesirable shocks and vibrations.
In order to facilitate the removal of the cage from the chassis, the cage is advantageously disposed on sliding rails that are connected to the chassis, for example. Thus, when it is desired to access the components disposed within the cage, the cage is simply slid in a horizontal direction out of the chassis.
In a further exemplary embodiment of the invention, and in order to reduce electromagnetic emissions, an electromagnetic shield is preferably permanently mounted to a rear of the cage. The electromagnetic shield advantageously automatically engages with the chassis, when the cage is disposed within the chassis, and automatically disengages with the chassis when the cage is removed from the interior thereof.
In another exemplary aspect of the present invention, and to facilitate the electrical connections between the components of the cage and those disposed within the chassis, the cage and chassis are provided with an autodocking feature that automatically couples the backplane, for example, with the components within the chassis. In this exemplary embodiment, the autodocking feature includes one or more plugs, for example, disposed within or on the cage and coupled to the backplane. The plugs are positioned against the outside surface of the front wall of the cage and/or positioned within the cage and adjacent to an opening formed through the front wall of the cage. Moreover, one or more receptacles can be provided within the chassis. When the cage is fully received within the chassis, the receptacles engage with the respective plugs, thereby automatically electrically coupling the backplane with other components disposed within the chassis. Likewise, when the cage is slid out of the chassis, the plugs automatically disengage with the respective receptacles, thereby uncoupling the backplane from the other components disposed within the chassis. This arrangement advantageously eliminates the need to manually disconnect various electrical connections between the cage and the chassis, when the cage is removed.
Furthermore, the sliding rails ensure that the cage is properly positioned and automatically aligned relative to the chassis during the autodocking procedure. Thus, the respective electrical connections can be coupled together automatically, reliably, and quickly.